Animation stops abruptly

[Spoonrad]

Hello,

I'm having a specific issue in implementing PulsingHalo in my project. I don't think the issue is specifically related to PulsingHalo, but I'm at a loss for a solution. I've opened a StackOverflow question on this, if you would be okay with taking a look.
http://stackoverflow.com/questions/35844295/ios-layer-animation-stops-abruptly

The basic problem is that the animation, for some reason, starts fine for a few seconds then suddenly completely stops for a second or two, then restarts normally, over and over.